KR20040093073A - Catalyst for removing nitrogen oxides, method for production thereof and method for removing nitrogen oxides - Google Patents

Abstract

Disclosed is a method for producing a catalyst for removing nitrogen oxides which comprises dispersing a hydrated titanium (Ti) oxide or dried material thereof, tungstic acid or a salt thereof, and cerium (Ce) dioxide in a dispersion medium to form a sol-like material, mixing the sol-like material with an aqueous medium to form a catalyst slurry or paste, supporting the catalyst slurry or paste on a catalyst carrier, and then calcinating the carrier; in which catalyst the Ce dioxide is prevented from being embedded in the Ti oxide to realize such a high degree of dispersion of the Ce dioxide on the surface of the Ti oxide as comparable with the case wherein cerium ions are dispersed in micro voids of a zeolite by ion exchange; and the catalyst is free from the occurrence of such phenomena as sintering of the Ti oxide, and deterioration of zeolite with steam when a zeolite is used as carrier. <IMAGE>

Description

Catalyst for nitrogen oxide removal, its manufacturing method, and nitrogen oxide removal method {CATALYST FOR REMOVING NITROGEN OXIDES, METHOD FOR PRODUCTION THEREOF AND METHOD FOR REMOVING NITROGEN OXIDES}

In the United States and the like where power consumption is large, so-called simple cycle gas turbine power generation, in which gas turbines are constructed and operated independently to compensate for power shortages or to cope with peaks in power consumption, is increasing. Since the facilities used for these power generation are constructed outside the city suburbs, the NOx contained in the exhaust gas is also high and needs to be decomposed and purified. However, in a simple cycle gas turbine power generation, it is necessary to install a denitrating apparatus immediately after the exit of each gas turbine and treat the exhaust gas at a high temperature of 450 ° C to 600 ° C. Denitrification catalysts with performance and long life have not been known to date. In particular, in the high temperature region, since the activity deterioration of the catalyst due to thermal deterioration is remarkable, an exhaust gas of around 350 ° C. discharged from the boiler using a low activity catalyst having improved heat resistance at the expense of the catalyst activity is used. The exhaust gas treatment had to be filled with several times the amount of catalyst used for denitrification. For this reason, in order to cope with the peak of electric power consumption, it is necessary to provide a large denitrification facility in the facility which has a short annual operating time, and it is also a big burden economically.

Accordingly, many studies and inventions have been made on catalysts that are difficult to deteriorate at high temperatures. Particularly, it is known that catalysts containing cerium (Ce) as an active component exhibit relatively high performance even at high temperatures. For example, Japanese Patent Application Laid-Open No. 08-257402, a soluble titanium (Ti) compound, tungsten (W) compound and cerium (Ce) compound are obtained by coprecipitation and particles of Ce compound are obtained. Highly dispersed catalysts in titania are disclosed. In addition, Japanese Patent Application Laid-Open No. Hei 08-27408 discloses a catalyst in which Ce ions are dispersed in zeolite pores by ion exchange method to achieve high activation and stabilization. These catalysts have an excellent aspect in terms of stabilizing and activating the catalyst by dispersing Ce, which has long been known as an active ingredient of the catalyst, in the catalyst. However, the present inventors have high activity and improved heat resistance in the high temperature region. From the point of view of providing a catalyst having the above, there are problems left to be improved.

Among the prior arts described above, the method of preparing a catalyst by precipitating soluble compounds of Ti, W and Ce by coprecipitation has the following problems.

(1) As a premise, Ti and Ce are the same tetravalent atoms, and each compound containing one of these two elements is likely to take the state of being uniformly dispersed with each other when they are mixed. Therefore, when mixed, the compounds form a state in which a large amount of Ce compound (oxide) is buried in the Ti compound (oxide), so that the excellent activity possessed by the Ce compound could not be sufficiently utilized. This can be seen from the fact that it is difficult to separate the two compounds from each other, and Ce oxide frequently remains as an impurity close to 1% in industrial titanium oxide.

(2) In addition, since the precipitate obtained by the coprecipitation method is a gel, which is difficult to filter, it is necessary to process the gel precipitate through a large number of complicated processes until it can be practically used as a solid catalyst. There is a difficulty that this becomes high.

In addition, in the method of highly dispersing Ce ions into the zeolite pores, a catalyst having extremely high initial performance can be obtained, but so-called dealuminum (de-) in which aluminum in the zeolite is separated from the zeolite structure into the zeolite pores. The catalyst is likely to deteriorate due to the aluminum phenomenon. In particular, since the dealumination phenomenon is promoted by the temperature and the presence of water vapor, when the catalyst is used for high temperature denitrification which exposes the catalyst for a long time in the exhaust gas containing 5 to 10% of water vapor, it is possible to maintain high catalytic activity over a long period of time. Is difficult.

In view of the problems with the prior art, the object of the present invention is to prevent Ce oxide from being buried in Ti oxide, and can be compared with the case where Ce ions are dispersed in pores of zeolite on the surface of titanium oxide by ion exchange method. The present invention provides a denitration catalyst which realizes a high degree of high dispersion of Ce oxide and prevents phenomena such as sintering of titanium oxide and deterioration of zeolite by water vapor, for example, a simple cycle gas. The present invention provides a method for detoxifying NOx in hot exhaust gas discharged from a facility such as a power generation facility using a turbine power generation facility or the like.

The present invention relates to a catalyst used for removing nitrogen oxides (NOx) contained in exhaust gas and a method for producing the catalyst, and in particular, a catalyst for efficiently removing NOx contained in hot exhaust gas of 450 ° C. or higher, A method for producing a catalyst and a method for removing NOx contained in exhaust gas.

1 is a conceptual diagram of a catalyst structure showing the spirit of the present invention.

2 is a conceptual diagram of a conventional catalyst structure.

3 is a graph showing the effect of the present invention comparing the denitrification rate of the catalyst of the Example and Comparative Example.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched and developed the catalyst which made the titanium oxide main component the remarkably improved both heat resistance and activity, and came to the following conclusion.

(1) In order to dramatically improve the activity of the catalyst, it is an effective means to improve the contact between Ce ions or Ce oxides and gas by highly dispersing Ce ions or Ce oxides in micropores such as zeolite micropores.

(2) For the purpose of high dispersion, when the Ti and Ce compounds are mixed under conditions that can be easily mixed, the mixing proceeds excessively because the properties of these two compounds are similar, and thus the Ti compound (for example, TiO ₂ Since Ce compound is buried in the C), contact between Ce compound and exhaust gas is inhibited, and Ce compound does not function as an active ingredient. In addition, since the sintering of TiO ₂ is accelerated by the Ce compound, this mixture is not suitable for use as a high temperature catalyst.

Therefore, the present inventors have made a bridge between intensive research as a result, when mixing the TiO ₂ and tungstic acid or a salt thereof with the hydroxyl groups on the surface in the presence of water, acid is a hydroxyl group and tungsten of TiO ₂ fused to TiO ₂ crystals makin, when firing the catalyst, FIG. 1 (a) micro holes are formed with a diameter of 50Å or less comparable in the zeolite pores, as shown in, the formation of the titanium oxide having such fine pores, the fine particles, but of TiO ₂ when coexist inside the sol of which can not be penetrated CeO _2, also because into micropores formed between the isolated TiO ₂ determined by a W compound as shown in 1 (b) CeO ₂ enters invasive as an active ingredient The present invention has been found by discovering that high heat resistance and high activity are imparted to the resulting catalyst.

According to the catalyst of the present invention, as shown in the conceptual diagram of the catalyst shown in FIG. 1 (b), TiO ₂ crystals are tungsten acid or tungsten trioxide (WO ₃ ) sandwiched between crystals to orient and aggregate to form fine pores. forming, and the active ingredient of Ce by the particles of the compound present in the gap between the TiO ₂ crystals, TiO ₂ crystals to prevent contact dispersing Ce ions by the addition, ion exchange method, and also inhibit the growth of the TiO ₂ crystals by heat between Achieve high catalytic activity similar to that of the prepared zeolite, and at the same time, the phenomenon of zeolite deterioration can be completely prevented when the zeolite is exposed to a gas containing water vapor at a high temperature.

In the present invention, the Ce compound as the active component is required to exist in the gap between the TiO ₂ crystals as shown in Fig. 1 (b). On the other hand, when TiO ₂ and Ce oxide are mixed in a highly reactive soluble salt or ion state, particles of Ce oxide are buried in TiO ₂ and do not exist in micropores, so only a low-performance catalyst is obtained. do.

In summary, the present invention is as follows.

(1) A catalyst slurry or paste obtained by mixing a hydrous titanium oxide or its dried body, tungstic acid or its salt, and a sol state in which a cerium dioxide is dispersed in a dispersion medium and an aqueous medium is supported on a catalyst carrier. And then calcining the catalyst carrier.

(2) The method for producing a catalyst for removing nitrogen oxides according to claim 1, wherein the catalyst slurry or paste further contains colloidal silica.

(3) The method for producing a catalyst for removing nitrogen oxides according to claim 1 or 2, wherein the catalyst slurry or paste further contains oxalic acid.

(4) The method for producing a catalyst for removing nitrogen oxides according to any one of items 1 to 3, wherein the catalyst slurry or paste further contains inorganic short fibers.

(5) The method for producing a catalyst for removing nitrogen oxides according to any one of items 1 to 4, wherein the catalyst carrier is an inorganic fiber catalyst carrier, a ceramic catalyst carrier or a metal carrier.

(6) The corrugatred honeycomb carrier according to item 5, wherein the inorganic fiber catalyst carrier is prepared by corrugating a sheet made of silica-alumina-based inorganic fibers. Method for producing a catalyst for removing nitrogen oxides, characterized in that.

(7) The method for producing a catalyst for removing nitrogen oxides according to claim 5, wherein the metal catalyst carrier is metal lath.

(8) A catalyst for removing nitrogen oxides produced by the method according to any one of items 1 to 7.

(9) A method for removing nitrogen oxides, wherein the nitrogen oxides are removed from the exhaust gas containing nitrogen oxides using the catalyst according to item 8 in the presence of ammonia.

(10) The method for removing nitrogen oxides according to claim 9, wherein the temperature of the exhaust gas is 350 to 600 ° C.

(11) The method for removing nitrogen oxides according to claim 9, wherein the exhaust gas is a gas turbine exhaust gas.

The present invention typically includes i) oxo acid (oxo) of tungsten (W) in a slurry of hydrous titanium oxide, such as metatitanic acid or ortho titanic acid, its dried body, or a colloid such as titania sol. -acid) or salts thereof, and a sol obtained by dispersing cerium dioxide with an aqueous medium, and ii) a sol produced in i), a pH adjuster such as oxalic acid or acetic acid or a binder such as silica sol, if necessary. Iii) a slurry or paste (hereinafter referred to as " catalyst slurry " or " catalyst paste ") was prepared by mixing an aqueous medium with the sol, and iv-a) a honeycomb obtained by corrugating a sheet made of inorganic fibers. Shape carrier, inorganic fiber non-woven sheet carrier, honeycarm carrier made of ceramics such as cordierite or alumina, reticulated material such as gold mesh or metal lath, E-glass fiber yarn (E mesh inorganic fiber yarns, such as glass fiber yarns Impregnated with a catalyst carrier or a catalyst paste such as a network woven into a catalyst slurry, iv-b) coating a catalyst slurry or a catalyst paste on the catalyst carrier, or iv-c) a catalyst slurry or a catalyst paste After rolling and apply | coating to fill the eyes of water, v) drying and baking were performed.

The titanium oxide raw material used in the present invention may be any one having a hydroxyl group on the surface of the titanium oxide, and specifically, a hydrous titanium oxide, a sol state of titanium oxide, a dried body thereof, or the like can be used. For example, one may contain sulfuric acid radicals as impurities, such as a dried body produced from metatitanic acid obtained by the sulfuric acid method.

As the tungsten (W) raw material, an oxo acid or heteropolyacid containing an MO ₄ type ion (M: W) of the corresponding metal (M), or an ammonium salt such as meta or ammonium paratungstate can be used. . The addition amount of the tungsten raw material to a catalyst is 1-20 atomic%, Preferably it is 5-15 atomic%. A small amount of tungsten causes deterioration of heat resistance, while an excessively large amount of tungsten reduces the proportion of titanium oxide retaining the active ingredient, leading to a decrease in activity.

On the other hand, the cerium oxide sol substance is obtained by dispersing CeO ₂ in water containing an organic alkali or an acid as a stabilizer, and commercially available UV absorbers and coating agents may be used. The addition amount with respect to a catalyst is 0-10 atomic%, Preferably it is the range of 1-5 atomic%. When the addition amount is too small, high activity is hard to be obtained. When the addition amount is too large, the activity deterioration at 500 ° C or more is likely to occur.

Addition of oxalic acid or acetic acid is not necessary, but in the case of using an ammonium salt of tungstic acid, the acid reacts with ammonium ions to form tungstic acid, which promotes the adsorption of tungstic acid to titanium oxide, and is added as necessary. In particular, oxalic acid has a property of slightly dissolving titanium oxide, and activates the surface of titanium oxide to promote reaction with tungstic acid. Therefore, it is easy to obtain good results by adding 5 to 10 wt% of titanium oxide.

As a catalyst carrier carrying the catalyst slurry or the catalyst paste containing the above compounds, as described above, a honeycam carrier obtained by corrugating a sheet made of an inorganic fiber, a nonwoven fabric made of an inorganic fiber, a network such as gold mesh or metal lath, Reticulated nets of inorganic fiber yarns, such as E-glass fiber yarns, are used, and these carriers can be reinforced with known reinforcing agents, to increase adhesion of catalyst components or to prevent oxidation of metal substrates. You may form and use the target coating layer.

Any method of supporting the catalyst slurry or catalyst paste may be used, but the fiber gap may be immersed in a slurry containing 30 to 50 wt% of a catalyst component in an inorganic fiber corrugated honeycomb, a ceramic nonwoven fabric, and a ceramic honeycomb carrier. It is suitable to fill the catalyst slurry with or to coat the catalyst slurry on the carrier surface. On the other hand, in the case of using a metal or ceramic network, when the eyes of the mesh are small, in addition to the coating method described above, inorganic fibers were added to the catalyst paste having a moisture content of 30 to 35% using a roller. The method of apply | coating so that the eye of a network may be filled may be employ | adopted.

The catalyst slurry or the catalyst paste supported on the various substrates by the above method is subjected to treatment such as cutting, molding, deformation, etc. as necessary, and then dried by a known means such as air drying or hot air drying. It is calcined at ˜700 ° C. and used as a catalyst.

The catalyst of the present invention is suitably used for removing NOx in a high temperature exhaust gas, for example, 350 to 600 ° C, preferably 450 to 600 ° C, most preferably 500 to 600 ° C.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail using a specific example. However, the scope of the present invention is not limited by these embodiments.

(Example 1)

80 g of low temperature dry titanium oxide (manufactured by Millennium, trade name: G5, surface area 275 m ² / g), and aqueous ammonium metatungstate solution [(NH ₄ ) ₆ H ₂ W ₁₂ 0 ₄₀ x H ₂ 0, 50 wt% as WO ₃ Concentration] 52.7 g, CeO ₂ sol (manufactured by Daiko Chemical Co., Ltd .; trade name: Nidoral, CeO ₂ content 15 wt%), 26.2 g, oxalic acid 4 g, silica sol (manufactured by Nippon Chemical Co., Ltd .; 50 g of OS sol, 20 wt% of concentration) and 50 g of water were mixed to prepare a catalyst slurry having a TiO ₂ concentration of about 30 wt%.

The catalyst slurry thus obtained was immersed by cutting aluminosilicate-based inorganic fiber corrugated honeycam (No. 3722, manufactured by Nichias Co., Ltd.) at a width of 5 cm in length, and supported on the surface of the inorganic fiber and on the fiber surface. After drying, the catalyst was calcined at 600 ° C. for 2 hours to prepare a catalyst.

In this case, the supported amount of the catalyst was 300 g / L, and the chemical composition was 88/10/2 in terms of Ti / W / Ce atomic ratio.

(Examples 2 and 3)

The amounts of the aqueous ammonium metatungstate solution and CeO ₂ sol in Example 1 were changed to 83.8 g and 27.6 g (Example 2), and 24.9 g and 24.8 g (Example 3), respectively, and were added in each example. by adjusting the amount of water to prepare a catalyst by the same manner as in example 1 except that the catalyst slurry TiO ₂ concentration of about 30wt%.

The chemical compositions of the catalyst thus obtained were 83/15/2 (Example 2) and 93/5/2 (Example 3) in terms of Ti / W / Ce atomic ratio.

(Examples 4 to 6)

The amount of the ammonium metatungstate aqueous solution and CeO ₂ sol added in Example 1 was 52.1 g and 12.9 g (Example 4), 53.3 g and 39.7 g (Example 5), 54.9 g and 67.8 g (Example 6), respectively. ), And the catalyst was prepared in the same manner as in Example 1 except that the amount of water added in each Example was adjusted to adjust the TiO ₂ concentration to about 30 wt%.

The chemical compositions of the catalyst thus obtained were 89/10/1 (Example 4), 87/10/3 (Example 5), and 85/10/5 (Example 6) by Ti / W / Ce atomic ratio. .

(Comparative Example 1)

A catalyst was prepared in the same manner as in Example 1 without adding CeO ₂ sol in Example 1.

(Comparative Example 2)

9.9 g of CeO ₂ sol in Example 1 was changed to cerium nitrate [Ce (NO ₃ ) ₃ .6H ₂ 0], and the chemical composition of the catalyst was changed to Ti / W / The catalyst which is 88/10/2 by Ce atomic ratio was prepared.

(Comparative Example 3)

Hydrogen-substituted mordenite (Tosoh Co., Japan, Si / Al ratio: 23.1) 100 g and cerium nitrate [Ce (NO ₃ ) ₃ ㆍ 6H ₂ 0] were dispersed in 200 g of water. The dispersion was evaporated to dryness in a sand bath, and then calcined at 550 ° C. for 2 hours to prepare Ce-substituted mordenite (3 wt% Ce ion).

The Ce-substituted mordenite powder thus obtained was dispersed in a mixed solution of 100 g of silica sol (manufactured by Nippon Chemical Co., Ltd .; trade name: OS sol, concentration 20 wt%) and 100 g of water to prepare a catalyst slurry.

The catalyst slurry thus obtained was immersed by cutting the aluminosilicate-based inorganic fiber corrugated honeycomb (No. 3722, Nichias Co., Ltd., 5 cm in length and length, respectively) between the inorganic fibers and on the surface of the fiber, followed by 150 ° C. Dried at and then calcined at 600 ° C. for 2 hours to prepare a catalyst.

For the catalysts prepared in Example 1 and Comparative Examples 1 to 3, the denitrification rate of the exhaust gas at 350 to 600 ° C. was measured under the conditions shown in Table 1 in the presence of ammonia.

Table 1

Item shame Space velocity SV 60,000 l / h 2. Gas composition NH ₃ 240 ppm NO 200 ppm O ₂ 10% CO ₂ 5% H ₂ O 5%

The obtained result is shown in FIG. From the results shown in FIG. 3, the catalyst of Example 1 of the present invention has extremely high performance compared to the catalyst of Comparative Example 1 having a chemical composition of Ti / W and the catalyst of Comparative Example 2 using cerium nitrate as Ce raw material. It is found that the catalyst is a highly active catalyst comparable to that of the Ce-substituted zeolite prepared in Comparative Example 3.

On the other hand, for the catalysts of Examples 1 to 6 and Comparative Examples 1 to 3, the heat resistance test maintained at 550 ° C. for 200 hours in the air and the gas having a H ₂ 0 concentration of 30% shown in Table 2 at 200 ° C. for 200 hours. A steam resistance test was performed. The denitrification performance was measured under the conditions of Table 1 for the catalysts after these tests. In the obtained performance, the value after an initial stage, a heat test, and a water vapor test at 550 degreeC was shown compared with Table 3.

TABLE 2

Item shame Space velocity SV 60,000 l / h 2. Gas composition O ₂ 20% H ₂ O 30%

TABLE 3

catalyst Early stage After heat test After domestic steam test Example 1 85.6 83.2 84.5 Example 2 79 79.2 79.7 Example 3 82.1 82.7 82.9 Example 4 83.1 81.4 82 Example 5 80.5 79.8 78.8 Example 6 78 78.1 77.9 Comparative Example 1 65.6 63.2 63.5 Comparative Example 2 70.1 71.3 69.4 Comparative Example 3 93.8 91.5 32.2

As is apparent from Tables 2 and 3, the catalysts of Examples 1 to 6 of the present invention not only have a high performance as compared to Comparative Examples 1 and 2, but also hardly exhibit a deactivation even by a heat test and a steam test. It is obvious to have good durability. On the other hand, the Ce-substituted mordenite catalyst shown in Comparative Example 3 had a value which is inferior to the performance of the catalyst of the present invention at the initial performance and the heat resistance, but the steam vapor test exposed to an atmosphere having a water vapor concentration of 30% Afterwards, the activity was markedly lowered, showing the lowest value among the catalysts of the examples as well as the comparative catalysts.

From these results, the catalyst of the present invention not only has high high temperature denitrification performance, but also a catalyst having excellent heat resistance and water vapor resistance, and thus can be said to exhibit the effect of the present invention.

On the other hand, when Examples 1, 2, and 3 were compared, it turned out that the performance tends to fall even if there is little or too much W content in a catalyst. In addition, from the comparison of Examples 1 and 4 to 6, when the amount of Ce added is too large, the heat resistance tends to decrease, and it can be seen that 5 atomic% or less is preferable as the amount of addition.

(Example 7)

15 kg of titanium oxide (manufactured by KKK, specific surface area 250 m ² / g), 9.7 kg of ammonium metatungstate, 4 kg of CeO ₂ sol, 0.8 kg of oxalic acid and 2 kg of water are kneaded and kneaded for 20 minutes. 4 kg of silica-alumina-based ceramic fibers (manufactured by Toshoku Co., Ltd .; trade name: Fineflex) were slowly added while kneading for 30 minutes to obtain a catalyst paste having a water content of 32%.

The catalyst paste thus obtained was placed on a substrate subjected to metal lath processing with a 0.2 mm thick SUS304 steel sheet, sandwiched between two polyethylene sheets, and passed through a pair of pressure rollers to form a metal lath substrate. The catalyst paste was apply | coated between the meshes and the surface of this. After drying this, it baked at 600 degreeC for 2 hours, and obtained the plate-shaped catalyst.

The denitrification rate of the catalyst thus obtained was measured at 550 ° C. under the condition of an area speed of 51 m / h, and the denitrification rate was 75%. This value corresponds to 83% of the denitrification rate at SV = 60,000 l / h in Example 1, wherein the catalyst prepared by the method of the present invention exhibits high performance at high temperatures despite the method of supporting the catalyst on a carrier. To indicate that

According to the inventions of claims 1 to 7, the catalyst for nitrogen oxide removal which is highly active and excellent in heat resistance can be obtained, and NOx in hot exhaust gas, such as gas turbine exhaust gas, which does not have a high recovery steam generator (HRSG). Can be efficiently purified. In addition, the method of the present invention can be obtained in a very small process such that the catalyst raw material is supported on various carriers after mixing, without requiring complicated steps such as precipitation operation such as coprecipitation method. This is connected with the social effect of providing an inexpensive and excellent exhaust gas purification device and contributing to environmental improvement.

According to the invention described in Claim 8, by using a highly active catalyst, a compact denitrification apparatus can be realized, and the reactor made of an expensive material requiring heat resistance can be made smaller and lighter.

According to invention of Claims 9-11, nitrogen oxide in high-temperature exhaust gas can be removed at high efficiency.

Claims (11)

A catalyst slurry or paste obtained by mixing an aqueous medium with a hydrous titanium oxide or a dried body thereof, tungstic acid or a salt thereof, and a sol state in which a cerium dioxide is dispersed in a dispersion medium is supported on a catalyst carrier. A method for producing a catalyst for removing nitrogen oxides, comprising firing a catalyst carrier. The method for producing a catalyst for removing nitrogen oxides according to claim 1, wherein the catalyst slurry or paste further contains colloidal silica. The method for producing a catalyst for removing nitrogen oxides according to claim 1 or 2, wherein the catalyst slurry or paste further contains oxalic acid. The method for producing a catalyst for removing nitrogen oxides according to any one of claims 1 to 3, wherein the catalyst slurry or paste further contains inorganic short fibers. The method for producing a catalyst for removing nitrogen oxides according to any one of claims 1 to 4, wherein the catalyst carrier is an inorganic fiber catalyst carrier, a ceramic catalyst carrier or a metal carrier. 6. The inorganic fiber catalyst carrier is a corrugatred honeycomb carrier prepared by corrugating a sheet of silica-alumina inorganic fiber. A method for producing a catalyst for removing nitrogen oxides. The method for producing a catalyst for removing nitrogen oxides according to claim 5, wherein the metal catalyst carrier is metal lath. The catalyst for nitrogen oxide removal manufactured by the method in any one of Claims 1-7. A method for removing nitrogen oxides, wherein the nitrogen oxides are removed from the exhaust gas containing nitrogen oxides using the catalyst of claim 8 in the presence of ammonia. The nitrogen oxide removal method according to claim 9, wherein the temperature of the exhaust gas is 350 to 600 ° C. 10. The method of claim 9, wherein the exhaust gas is a gas turbine exhaust gas.